Even with dual-mode uboot, the optical module’s EEPROM often contains a vendor ID and mode flag. Use i2cget and i2cset commands in Linux shell (after boot):
Fiber optic forums often have swap groups. Trade your GPON device for someone’s EPON unit. firmware huawei hg8245h gpon to epon
The conversion typically requires a specific "Flasher" tool and the corresponding EPON-compatible firmware file. Even with dual-mode uboot, the optical module’s EEPROM
For 99% of users, buying the correct native EPON ONT is cheaper, faster, and safer. However, if you are an embedded systems enthusiast with a serial console, a backup plan, and a tolerance for bricked devices, exploring dual-mode bootloaders can be a fascinating weekend project. Even with dual-mode uboot